1. Field of the Invention
The invention relates to an electronic drum, and more particularly, to an electronic drum comprising a pad having a batter head, and a rim provided around the pad, for detecting a strike respectively, thereby producing electronic sounds differing from each other.
2. Description of the Related Art
An electronic drum as an electronic percussion instrument is a percussion instrument wherein when an electronic drum pad (a batter head) is struck with a stick (drumstick), and so forth, a strike condition, such as stress of a strike, and so forth, is detected by an strike sensor made up of a piezoelectric transducer, and so forth, provided on the back side of the pad, and an electronic tone is produced by an electronic sound generator based on a detection signal from the strike sensor. Further, with a plurality of electronic drums in combination, it is possible to make up an electronic drum set similar to an acoustic drum set made up of acoustic percussion instruments.
Now, a drum as an acoustic percussion instrument is generally structured such that a membrane-like head (batter head) is stretched over an opening edge of a cylindrical shell (body), and the outer edge of the head is pressed with an annular rim (frame) to be secured to the opening edge, and when playing the drum (particularly, in the case of a snare drum), besides an ordinary style of playing for striking the head, there are a style of playing for striking only the rim to produce a hard tone, and a style of playing, called a rim-shot (an open-rim-shot) for striking the head and the rim with a drumstick substantially at the same time, thereby producing unique harmonics of the drum.
A variety of electronic drums with a rim having a dedicated strike sensor, provided around a pad, which is a batter head, have so far been offered, including an electronic drum producing only a rim strike sound differing from a head strike sound, and an electronic drum producing a strike sound corresponding to the rim-shot.
For example, in JP H9-198040A, there has been disclosed an electronic percussion instrument (electronic drum) capable of producing a large variety of tone colors due to relationships in timing between a striking force against a pad, and a striking force or a thrust force against a rim. With the electronic percussion instrument described, it is a precondition for producing a tone color for the open-rim shot playing by striking both the pad and the rim to detect a pad strike within a rim shot standby time (a predetermined time) from detection of a rim strike, as shown in FIG. 6. When the pad strike is detected after the elapse of the predetermined time, a tone color of the pad for a normal playing is produced.
Further, in JP H6-35450A, there has been disclosed an electronic percussion instrument (electronic drum) for causing a musical tone to be produced according to strike detection by a shock sensor of a pad (head), and controlling the musical tone according to an output from a pressure sensor of a rim. With the electronic percussion instrument described, it is a precondition for producing a tone color corresponding to the rim-shot to detect a pad strike within a process time from detection of a rim strike after the rim strike is detected, as shown in FIG. 7.
With the electronic percussion instrument (electronic drum) as disclosed in any of Patent Documents described as above, in order to produce the open-rim shot sound, it has been necessary to make a point of observing a sequence in which the rim is to be first struck followed by a strike of the pad (head), having had no such flexibility as in the case of an acoustic drum capable of producing a rim-shot sound even if the pad is struck slightly ahead, so that those electronic percussion instruments have had a problem in that it is harder to execute the rim-shot playing.
Furthermore, when the rim strike has been first detected, any of those electronic percussion instruments has been simply standing by, or executing the process for the detection until the elapse of the predetermined time or the process time after the detection, having remained in a soundless state producing no sound before determination has been made thereafter on whether or not the pad strike has occurred. Accordingly, there has arisen a problem in that when the rim strike is first detected, a slight delay time always occurs before a musical tone is produced, thereby causing an audience to have a sense of incompatibility at the time of a performance.